Field of the Invention
The present invention relates to a method for determining availability of an assigned machine to machine (M2M) group identifier by a machine to machine (M2M) terminal, and more particularly, to a method for determining whether to support a preassigned M2M group identifier based on a change of an M2M group zone identifier.
Related Art
Machine to machine (M2M) communication (machine type communication: MTC)
Hereinafter, a machine to machine (M2M) communication (machine type communication: MTC) will be described in brief.
The M2M communication means communication between electronic devices as a crude representation. That is, the M2M communication means communication between objects. In general, the M2M communication means wired or wireless communication between the electronic devices or communication between a device and a machine controlled by human, but the M2M communication is used as a meaning that particularly designates wireless communication between the electronic devices, that is, machines. Further, M2M terminals used in a cellular network have lower performance or capability than general terminals.
A lot of terminals are present in a cell and the terminals may be distinguished from each other according to a type, a class, a service type, and the like of the terminal.
As one example, the terminals may be classified into terminals for human type communication (HTC) and a machine type communication (MTC) according to operation types of the terminals. The MTC may include communication between the M2M terminals. Herein, the HTC means transmitting and receiving a signal by determination of signal transmission by human, and the MTC means that each terminal transmits a signal by even occurrence or periodically of itself without intervention by human.
In addition, when the M2M communication or the machine type communication (MTC) is considered, the number of all terminals may be rapidly increased. The M2M communication may have features described below depending on a service that supports the M2M terminals.
1. A lot of terminals in the cell
2. Small data amount
3. Low transmission frequency (may have periodicity)
4. Data characteristic of a limited number
5. Not sensitive to time delay
6. Low mobility or fixed
Further, the M2M communication may be used in various fields including a protection access and monitoring, tracking and discovering, public safety (an emergency situation and a disaster), payment (a vending machine, a ticket machine, and a parking meter), health care, remote control, a smart meter, and the like.
Idle Mode
An idle mode is a mechanism in which although a terminal wanders about a radio link environment where a plurality of base stations is present throughout a wide area, the terminal is capable of periodically receiving a downlink broadcast message without registration in a specific base station.
The idle mode represents a state in which all normal operations as well as handover (HO) stops and only downlink synchronization is adjusted so as to receive a paging message which is a broadcast message in only a predetermined interval. The paging message is a message that instructs the terminal to perform a paging action. For example, the paging action includes ranging execution, network reentry, and the like.
The idle mode may be started by the terminal or the base station. That is, the terminal transmits a deregistration request (DREG-REQ) message to the base station and receives a deregistration response (DREG-RSP) message from the base station in response thereto to enter the idle mode. Further, the base station transmits an unrequested deregistration response (DREG-RSP) message or a deregistration command (DREG-CMD) message to enter the idle mode.
In the idle mode, when the terminal receives the paging message corresponding thereto during an available interval (AI), the terminal transmits and receives data to and from the base station by switching the idle mode to a connected mode through a network entry process.